[PATCH] input: alps-fix the issue alps cs19 trackstick do not work.

From: XiaoXiao Liu
Date: Mon May 27 2019 - 05:47:42 EST


The alps devices which detected to use the ALPS_PROTO_V8 procotol contains
ALPS touchpad and ALPS trackstick.The ALPS_PROTO_V8 procotol do not
support the trackstick device process by default.

When the trackstick was detected to use ALPS_PROTO_V8 procotol,
the v8 process_packet method alps_process_packet_ss4_v2 will reject to
report the data when the device using ALPS_PROTO_V8 procotol is not set
the ALPS_DUALPOINT flag.

The alps cs19 trackstick is detected to use the ALPS_PROTO_V8 procotol
but without ALPS_DUALPOINT flag, the alps driver will not report the
input data. so the trackstick will not work.

solution: when the alps cs19 device detected, set the device
ALPS_DUALPOINT flag,then the input data will be processed.

Signed-off-by: XiaoXiao Liu <sliuuxiaonxiao@xxxxxxxxx>
---
drivers/input/mouse/alps.c | 25 +++++++++++++++++++++++--
1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/drivers/input/mouse/alps.c b/drivers/input/mouse/alps.c
index 0a6f7ca883e7..a54677cf7474 100644
--- a/drivers/input/mouse/alps.c
+++ b/drivers/input/mouse/alps.c
@@ -24,7 +24,7 @@

#include "psmouse.h"
#include "alps.h"
-
+#include "trackpoint.h"
/*
* Definitions for ALPS version 3 and 4 command mode protocol
*/
@@ -220,6 +220,23 @@ static bool alps_is_valid_first_byte(struct alps_data *priv,
return (data & priv->mask0) == priv->byte0;
}

+static int alps_check_cs19_trackstick(struct psmouse *psmouse)
+{
+ u8 param[2] = { 0 };
+ int error;
+
+ error = ps2_command(&psmouse->ps2dev,
+ param, MAKE_PS2_CMD(0, 2, TP_READ_ID));
+ if (error)
+ return error;
+
+ if (param[0] == TP_VARIANT_ALPS && param[1] & 0x20) {
+ psmouse_warn(psmouse, "It is alps cs19 trackstick");
+ return 0;
+ }
+ return -1;
+}
+
static void alps_report_buttons(struct input_dev *dev1, struct input_dev *dev2,
int left, int right, int middle)
{
@@ -2568,8 +2585,12 @@ static int alps_update_dual_info_ss4_v2(unsigned char otp[][4],
alps_exit_command_mode(psmouse);
ps2_command(ps2dev, NULL, PSMOUSE_CMD_ENABLE);

- if (reg_val == 0x0C || reg_val == 0x1D)
+ if (reg_val == 0x0C || reg_val == 0x1D) {
+ is_dual = true;
+ } else if (alps_check_cs19_trackstick(psmouse) == 0) {
+ //For support Thinkpad CS19 TrackStick
is_dual = true;
+ }
}
}

--
2.20.1